One idea could be a gamer who gets transported into the Fairy Tail world and has to use their gaming knowledge to complete quests. For example, they might know the best strategies for fighting certain monsters from playing the game, which gives them an edge in the Fairy Tail universe.
One idea could be an OC who is a master of virtual reality games in the real world and discovers that their skills translate into unique magic in the Fairy Tail universe. For example, they can use their strategic thinking from gaming to outwit opponents in battles.
One idea could be that the godlike gamer has the ability to enter different virtual worlds within the fanfiction realm. He could start in a medieval - style game world and use his unique skills to become a legend there.
One idea could be the SI (Self - Insert) character using their gamer knowledge to unlock unique powers in the Highschool DxD universe. For example, they might figure out a way to level - up their devil or angel abilities like in a game. Another plot could involve the SI character forming a special team with the existing characters in the series to compete in some sort of supernatural gaming tournament within the DxD world. This could bring in new challenges and alliances.
One idea could be a gamer who gets sucked into the Fairytail world and starts to form a harem among the female characters. For example, he could use his gaming skills to impress them during battles. Maybe he masters a unique magic that no one in Fairytail has seen before, which draws the attention of Erza, Lucy, and other female mages. Another plot could be that he has to complete a series of in - game - like quests in the Fairytail world to win the hearts of the harem members. He might have to defeat a powerful dark guild while also dealing with the romantic interests of the girls.
One common theme is power - up. The self - inserted gamer often gains unique powers or abilities within the Fairy Tail world, which is related to their gamer status. Another theme is relationship building in the harem. There are usually multiple romantic or close relationships developing between the main character and the Fairy Tail characters.
One idea could be a new character arriving at Fairy Hills and having to adapt to the unique living situation. They could face challenges like getting along with the different personalities of the Fairy Tail mages living there.
A third plot twist could be that the harem itself is not what it seems. There could be a member of the harem who is secretly working against the main character under the influence of a dark force. This betrayal could send shockwaves through the group and force the reincarnated gamer to re - evaluate his relationships and alliances.
In 'naruto gamer si fanfiction', often there are interesting takes on the world - building. The gamer element can introduce things like in - game inventory systems into the Naruto world. So the character might be able to store kunai or scrolls in an inventory like in a game. Also, there could be quests or missions that are designed in a more game - like fashion which add a new layer of adventure to the Naruto story.
One idea could be Metalicana's backstory before he was known in the Fairy Tail world. Maybe exploring his early days as a dragon, his first encounters with other dragons or magical creatures. Another plot could involve Metalicana having a secret mission that is related to the future of the dragon slayers in Fairy Tail. It could also be interesting to have a plot where Metalicana has to team up with some of the Fairy Tail members in a time - travel adventure to save the past and thus ensure the future of the guild.
Another plot could involve a dark mage in the Fairy Tail universe summoning Deathwing to gain power. But the summoning goes wrong and Deathwing is only partially summoned. This weakened Deathwing starts causing destruction while also being hunted by Fairy Tail. The guild then has to decide whether to try and fully summon him to send him back or find another way to deal with him.